Spesifikasi HI84500 01
PH Meter
Details
The HI84500 can be used to test for free and total sulfur dioxide in all wines, including red, which are difficult to test using traditional methods due to the inability to see the distinctive color change that occurs at the endpoint. The HI84500 offers reliable, accurate, and fast wine analysis. This mini titrator dispenses the titrant, detects the endpoint, and performs all necessary calculations automatically in a fraction of the time as compared to a manual titration. As found in Triage for Basic Wine/Grape Lab by Richard Carey, “the mini-titrator by Hanna reduces the time for an individual analysis by 75%.”
Winemakers add sulfur dioxide (SO2) to wine in order to inhibit bacteria and wild yeast growth and to serve as an antioxidant to prevent browning. When SO2 is added to wine, a portion of it becomes immediately bound while a remaining portion is unbound SO2. The portion that is unbound is also called free SO2 and it is responsible for protecting the wine. The bound and free SO2 together are referred to as total SO2. The relationship between the amount of SO2 added and the amount of free SO2 is complex, governed by the total amount of SO2 in the wine and the ability of compounds (e.g. sugars, aldehydes, keto acids, quinones, anthocyanin) to bind to the SO2. The exact relationship between free and bound SO2 will vary from wine to wine.
The amount of free SO2 depends on how much is added, how much was present before the addition, and how much was immediately bound. Free SO2 exists in two forms. The first form, bisulfite (HSO3-), is the predominant form but is relatively ineffective. The second form, molecular SO2, is the minor form and is responsible for protecting the wine. The amount of molecular SO2 available in wine is dependent upon the amount of free SO2 present and the pH. Typically 0.8 ppm of molecular SO2 provides adequate protection against bacteria growth and oxidation. In order to obtain this value for a wine sample that has a pH of 3.2 you would need 22 ppm of free SO2. If the pH was at 3.5 you would need double the amount of free SO2, 44 ppm.
|
pH |
3.0 |
3.1 |
3.2 |
3.3 |
3.4 |
3.5 |
3.6 |
3.7 |
3.8 |
3.9 |
|
Free SO2 |
14 |
18 |
22 |
28 |
35 |
44 |
55 |
69 |
87 |
109 |
Application-Specific ORP Electrode The HI84500 is supplied with the HI3148B ORP electrode featuring CPS™ technology to prevent the clogging of the reference junction. Conventional electrodes may clog quickly in samples such as wine that have a high suspended solids content. By design, the HI3148B ORP electrode utilizes a ground glass/PTFE sleeve junction which controls a steady, predictable flow of electrolyte solution, keeping the junction open. The hydrophobic properties of PTFE repel wetness and coatings.
Piston Driven Dosing Pump The heart of the HI84500 is the piston driven burette pump. This type of dosing system uses a motor in which each dose is very precisely controlled and the volume dispensed is accurately determined. The piston driven burette is controlled dynamically so that the volume of titrant being dosed is automatically adjusted based on a voltage response of the previous dose. This type of dosing speeds up the titration process by allowing for more titrant to be dosed at the start of the titration and then very small doses as the endpoint is reached.
Specifications
| Range | Low Range: 1.0 to 40.0 ppm of SO2; High Range: 30 to 400 ppm of SO2 |
|---|---|
| Resolution | Low Range: 0.1 ppm; High Range: 1 ppm |
| Accuracy (@25ºC/77ºF) | Low Range: 3% of reading or ±0.5 ppm, whichever is greater; High Range: 3% of reading or ±1 ppm, whichever is greater |
| Sample Volume | 50 mL |
| Methods | Ripper method |
| Principle | equivalence point redox titration |
| Pump Speed | 10 mL/min |
| Stirring Speed | 700 rpm |
| mV Range | -2000.0 to 2000.0 mV |
| mV Resolution | 0.1 mV |
| mV Accuracy (@25ºC/77ºF) | ±1.0 mV |
| Logging Data | up to 400 (200 titrations, 200 ORP/mV readings) |
| Electrode | HI3148B glass body ORP electrode with BNC connector and 1 m (3.3’) cable (included) |
| Environment | 0 to 50°C (32 to 122°F); RH max 95% non-condensing |
| Power Supply | 12 VDC adapter (included) |
| Dimensions | 235 x 200 x 150 mm (9.2 x 7.9 x 5.9”) |
| Weight | 1.9 kg (67.0 oz.) |
| Ordering Information | HI84500-01 (115V) sulfur dioxide meter is supplied with HI3148B ORP electrode, HI7082 electrode fill solution (30 mL), HI84500-50 low range titrant (230 mL), HI84500-51 high range titrant (230 mL), HI84500-55 calibration standard (120 mL), HI84500-60 acid reagent (230 mL), HI84500-61 alkaline reagent (120 mL), and HI84500-62 stabilizer packets (50 packets), 100 mL beakers (2), 20 mL beakers (2), scissors, dosing pump valve, 5 mL syringe, 1 mL plastic pipette, tube set (aspiration tube with titrant bottle cap and dispensing tube with tip), stir bar, cleaning solution sachets for wine deposits (2), cleaning solution sachets for wine stains (2), 12 VDC adapter and instruction manual. |
| Warranty | meter 2 years, probe 6 months |